Door latching apparatus

ABSTRACT

Door latching apparatus includes a cylinder lock having a translatable rod, a spring-loaded dead bolt and linkage means coupling the rod to the dead bolt to cause alternate retraction and extension of the bolt in response to operation of the lock. The linkage means includes a reverse-curve arm pivotally mounted between, and pivotally connected to, the rod and to a push-button having an inclined surface adapted to urge against a corresponding inclined surface of the dead bolt. The lock is rendered substantially pick-proof by the inclusion therein of a bifurcated plug having separate and independent inner and outer portions.

United States Patent 11 1 Cillick 51 Jan. 16, 1973' 541 11001: LATCHING APPARATUS [76] lnventorz' Herman Cillick, 82 Roundtop Road,

Warren Township, Somerset County', NJ. 07060 7 Filed:

Primary Examiner-Marvin A. Champion Assistant ExaminerWilliam F. Pate, III Attorney-Michael J. Urbano [57] ABSTRACT Door latching apparatus includes a cylinder lock having a translatable rod, a spring-loaded dead bolt and linkage means coupling the rod to the dead bolt to cause alternate retraction and extension of the bolt in response to operation of the lock. The linkage means includes a reverse-curve arm pivotally mounted between, and pivotally connected to, the rod and to a push-button having an inclined surface adapted to urge against a corresponding inclined surface of the dead bolt. The lock is rendered substantially pickproof by the inclusion therein of a bifurcated plug having separate and independent inner and outer. portions;

'13 Claims, 4 Drawing Figures PATENTEDJAN 16 I978 FIG. 2

FIG. 3

BY HERMAN C/LL ICK Z M ATTORNEY 1 noon LATCHING APPARATUS- BACKGROUND OF THE INVENTION ;This invention relates to door latching, apparatus,

and, more particularly, to such apparatus including a with numerous lock designs most of which fall into two basic categories: combination locks and key-operated locks. While combination, locks are frequently more pick-proof than key-operated locks, they have not received as widespread use due primarily to their increased complexity which often renders their cost prohibitive. On the other hand, most attempts at increasing the security of key-operated locks, such as double cylinder locks, have been disadvantageous not only from a cost standpoint but also because such locks are susceptible to being picked as well as to forcible entry (as by striking the cylinder and sleeve with a burglars tool to destroy its locking ability). Consequently, there is still a need for a lock which'is highly reliable, pick-proof and yet is simple and inexpensive to manufacture.

It is therefore one object of my invention to make a cylinder lock substantially pick-proof.

It is another object of my invention to use such a lock in a door latching arrangementwhich is easily installed.

1 It is yet another object of my invention to provide such an arrangement which requires little or no maintenance. I

,It is still another object of my invention toprovide such a latching arrangement which has enhanced security, is highly reliable and yet simple and inexpensive to manufacture.

SUMMARY OF THE INVENTION These and other objects are accomplished in accordance with an illustrative embodiment of my invention, a door latching arrangement comprising a springloaded dead bolt, a cylinder lock having a translatable rod responsive to operation of the lock, and linkage means coupling the rod to the dead bolt to cause alternate retraction and extension of the bolt in response to two-way translation of the rod.

The linkage means illustratively comprises a revere-' curve arm pivotally connected'to both the rod and to a first push-button having an inclinedsurface adapted to urge against a corresponding inclined surface of the dead bolt. The arm is pivotally mounted at a point between the rod and push-button;

The cylinder lock, with one important exception, is of a conventional variety including a sleeve, a springloaded cylinder translatable within the sleeve and a plug rotatably' mounted in the cylinder. Both the r cylinder and plug have a plurality of apertures for car-- ryingthe bifurcated pins which are aligned along the shear line by a key. In addition, the innermost end face of the plug has a cam thereon adapted to withdraw a lock bolt from a locking slot in the sleeve. In accordance with one feature of my invention, however, the cylinder includes a bifurcated plug having separate the outer portion, it is not possible for him to rotate the inner plug portion, hence, it is not possible for him to actuate the cam to withdraw the lock bolt.

In operation, the door is locked either by depressing the lock cylinder (from the'exterior) or by depressing the first push-button (from the interior). Both opera? tions actuate the linkage means simultaneously causing the dead bolt to-extend into a strike plate and causing the rod to extend and the cylinder lock bolt to snap into the locking slot. On the other hand, the door is opened from'the exterior by inserting a key into the cylinder lock plug which is then rotated one-quarter turn. This action causes withdrawal of, the lock bolt from the locking slot, retraction of the rod and actuation of the linkage means with consequent retraction of the dead bolt. From the interior, the door is opened by depressing a second push-button which causes the lock bolt to withdraw from the locking slot. The dead bolt then retracts in the same manner as described with respect to exterior key operation.

BRIEF DESCRIPTION OF THE DRAWING FIG. 3 is a cross-sectional view of an illustrative em-' bodiment of a cylinder lock in accordance with my inand independent inner and outer portions with an aligned slot extending axially therethrough to receive vention; and

FIG. 4 is an enlarged end view of the cam and lock bolt of FIG. 3.

DETAILED DESCRIPTION Turning now to FIGS. 1 and 2, there is shown in accordance with an illustrative embodiment of my invention, a door latching arrangement comprising a housing 10 mounted by screws or other fasteners (not shown) on the inside of door 11. Included in the housing 10 is a.

dead bolt 12 which is extendable into an opening 13 in registry therewith in door jamb 15 when the door 11 is closed. Also included in the housing 10 are a cylinder lock 14 mounted th rough the front plate 17a and door 11 via apertures therein in registry with one another,-'

and linkage means 16 coupling the lock 14 to the dead bolt 12.

The dead bolt 12 typically takes the form of a rectangular block having a channel 19 extending centrally therethrough and forming a U-shaped body having aninclined surface and leg portions 12b and 12. The

dead bolt 12 is spring-mounted typically by means of a pair of well-known spring-guide rod assemblies 36 36. Each assembly 36 has one end mounted in an aperture in a support block 37 affixed to the interior of the housing '10 and the other end affixed to one of the leg portions of the dead bolt 12. As shown, the bolt 12 preferably fits flush with the four sides or plates (17, 21) of housing 10, and when extended into opening 13 is urged inwardly by the springs of assemblies 36-36.

The linkage means 16 comprises a reverse-curve arm 25 pivotally connected at 27 in a slot in translatable rod 18 and at 29 in a slot in first push-button 20. The latter extends through the back plate 17b and has an inclined surface 20a adapted to urge against inclined surface 12a of dead bolt 12. In addition, the arm 25 is pivotally mounted on pin 31 which extends between top and bottom plates 21a and 21b, respectively, at a point between rod 18 and push-button 20.

The cylinder lock 14, as shown in FIG. 3, comprises a cylindrical sleeve 44 having a flange 46 for affixing the lock 14 to the front plate 170 of housing 10. Slidably mounted for translation in sleeve 44 is a cylinder 22 having rod 18 extending from the inner end thereof. The end 18a of rod 18, which has a slot 18b therein to receive arm 25, protrudes through the inner end of sleeve 44 into the interior of housing and translates in the direction of the arrow in FIG. 1. The cylinder 22 is also spring mounted by means well known such as by spring-guide rod assemblies 34 which urge the cylinder outwarding in the position shown (i.e., when locked). Assymmetrically disposed in an elongated aperture in cylinder 22 is a bifurcated plug 30 having separate and independent outer and inner portions 30a and 30b, respectively, axially aligned with one another. A relatively flat slot or keyway 35 extends axially through both plug portions, the cross-section of the slot 35 being shaped to fit a particular key 28 as is well known in the art. The innermost end face 32 of the plug (i.e., of portion 30b) has a protrusion or cam 33 which extends into a slot in lock bolt 24. The latter is positioned for radial motion in a groove in cylinder 22 and is spring loaded via spring 48. In the locked position, spring 48 urges the end tab portion 50 of lock bolt 24 through a locking slot 26 in sleeve 44. Spring 48 is inserted into an aperture in cylinder 22 and is then held in place by means of a cap 49 which typically forms a pressure fit in the aperture.

In each plug portion 30a and 30b there are a plurality of holes aligned with a corresponding plurality of holes in cylinder 22. Each such hole carries a bifurcated pin 52 and a spring 54 which urges each pin inwardly. As before, the springs are held in place by a pressure-fit cap 56. Six such pins are shown for the purposes of illustration only, the precise number being determined by design considerations. Moreover, only one of the plug portions need carry pins, not both, for the purposes of my invention. In addition, while the portions 52a-52 of each pin are shown for simplicity to be of respectively equal lengths, in general the lengths are unequal and are adapted so that key 28, when fully inserted into keyway 35, aligns each interface 520 between pin portions with the shear line 58. When so aligned the pins do not prevent rotation of the plug 30. Rotation ofthe latter, however, is typically limited to a quarter-turn by means of a protrusion 60 on the inner surface of cylinder 22 which rides in a circumferential groove 62 in outer plug portion 30a.

For reasons to be described hereinafter, housing 10 further includes, as shown in FIG. 2, a slidable covering 38 which exposes a second spring-loaded push-button 40 having a protruding member 41 adapted to push lock bolt 24 inwardly and out oflocking slot 26.

In operation, to lock the door from the outside key 28 is not needed. Locking occurs when cylinder 22 and plug 30, which translate together, are pushed inwardly against springs 34 until lock bolt 24 snaps into locking slot 26 under the urging of spring 48. This action causes rod 18 to translate inwardly and arm 25 to rotate counter-clockwise about pin 31 (as viewed in FIG. 1). Consequently, push-button 20 pushes against inclined surface 12a of dead bolt 12 causing it to slide to the right into opening 13 in door jamb 15. So positioned, the dead bolt is under tension from spring assemblies 36-36, but cannot be drawn inwardly until lock bolt 24 is released.

Similarly, to lock the door from the inside, again without the need for a key, the above sequence is reversed. That is, push-button 20 is pushed inwardly against dead bolt 12 causing it to slide to the right into opening 13. Simultaneously arm 25 rotates counterclockwiseabout pin 31 and rod 18 translates inwardlyuntil lock bolt 24 snaps into locking slot 26.

It should be noted that lock 14 is preferably mounted in the door 11 so that, when locked, the exterior portions of cylinder 22 are substantially flush with the outer surface of the door. This arrangement prevents a burglar from striking the lock with a chisel or other tool in order to gain entry.

On the other hand, to unlock the door from the inside, slidable cover 38 is moved to expose in base plate 21b an opening into which push-button 40 extends. One then inserts his finger into the opening to depress the push-button 40 against tab 50 of lock bolt 24 causing the latter to snap out of locking slot 26. Consequently, springs 34 push cylinder 22 outwardly causing rod 18 to translate outwardly, arm 25 to rotate clockwise about pin 31, push-button 20 to translate 'away from dead bolt 12 which withdraws from opening 13 thus unlocking the door.

In a similar fashion, to unlock the door from the out side, a key 28 is inserted into keyway 35 thus coupling together for rotation both portions 30a and 30b of plug 30. Then, the key 28 and plug 30 are rotated within cylinder 22 until post 60 strikes the end of circumferential slot 62. Rotation of plug portion 30b causes cam 33 to lift lock bolt 24 out of locking slot 26 and thus permits springs 34 to push cylinder 22 and rod 18 outwardly. Outward translation of rod 18, as before, rotates arm 25 clockwise about pin 31 causing pushbutton 20 to move away from dead bolt 12 which withdraws from opening 13 under the urging of spring assemblies 36-36.

The manner in which my latching arrangement, and more particularly lock 14, is rendered pick-proof is as follows. Consider that one with a burglars tool were successful in picking" pins 52 so that key 20 would not be needed to align the pins along the shear line and to rotate the plug 30. In a conventional cylinder lock in which plug 30 is a unitary assembly, such a person would then merely rotate the plug causing cam 33 to lift lock bolt 24 out of locking slot 26 to open the door. In accordance with my invention, however, plug 30 is bifurcated and such a burglar has access only to outer plug portion 300. Thus, even though the pins are picked, rotation of plug portion 30a does not rotate plug portion 30b and so lock bolt 24 cannot be withdrawn without a key which couples together 'por-- tions 30a and 30b.

It is to be understood that the above-described arrangements are merely illustrative of the many possible I specific embodiments which can be devised to represent application of the principles of the invention. Numerous and-varied other arrangements can be devised in accordance with'these principles by those skilled in the art without departing from the spirit and scope of the invention. In particular, while my latching arrangement. is shown in the foregoing to be mounted horizontally on a door, it could equally as well be mounted vertically. Moreover, for some applications, such as on the doors of commercial establishments, it may be advantageous to replace push-button with a cylinder lock so that the latching arrangement can be key-operated from both sides of the door.

Optionally, the cylinder lock 14 has an elongated slot 64 extending axially in sleeve 44 and adapted to receive the head ofa screw 23 which rides in slot 64 to limit the extent of the inward and outward translation of cylinder 22.

What is claimed is:

l. A latchingarrangement for a door or the like comprising a'housing mounted on the interior side of said door,

a dead bolt slidably disposed-in said housing and adapted to be alternately extended into and withdrawn from an opening in a door jamb or the like,

first lock means mounted in said door and having one end disposed exterior to said door and adapted to receive key means for unlocking said first lock means from the exterior side of said door, and

, further having the other end thereof disposed in- I terior to said housing, each of said ends being inwardly and outwardly translatable together in response to the locking and unlocking of said first lock means,

' first control means slidably mounted through a wall of said housing for applying a force to said dead bolt for extending same into said opening and for locking said first lock means from the interior side of said door, second control means mounted through said housing for unlocking said first lock means from the interior side of said door, and linkage means pivotallyconnected to both said first control means and said other end of said first lock means for extending said dead bolt in said opening I in response to inward translation of said other end of said first lock means and of said first control means.

2. The arrangement of claim 1 wherein 7 said dead bolt has an inclined surface disposed at an obtuse angle to the outward direction of its mo- 4. The arrangement of claim 3 including first spring means mounted in said housing for urging said dead bolt inwardly when in its extended position in said opening.

5. The arrangement of claim 4 wherein said dead bolt is U-shaped having a pair of leg portions and an inter mediate portion joining said leg portions, said intermediate portion including said inclined surface and said first spring means being connected to said pair of leg portions.

' 6. The arrangement of claim 2 wherein said first lock means comprises a first cylinder lock.

7. The arrangement of claim 6, wherein said first cylinder lock has a bifurcated plug adapted to receive said key means.

8. The arrangement of claim 7 wherein said first cylinder lock comprises an elongated sleeve rigidly mountedin said door and to said housing and having a circumferential locking slot,

a cylinder slidably mounted in one'end of said sleeve and having a rod extending from the other end of said sleeve, and the end of said rod comprising the other end of said-first lock means to which said linkage means is pivotally connected,

second spring means for urging said cylinder outwardly of said sleeve,

said cylinder having a plurality of radial apertures axially aligned with one another, and having further an elongated circular channel said cylinder, circular cylindrical plug means rotatably disposed in said'channel, said plug means comprisingseparate inner and outer plug portions axially aligned with one another and having an elongated keyway extending axially through said outer portion and at least into said inner portion for receiving said key means to couple together said plug portions for rotation,

at least one of said plug portions having a plurality of radial apertures axially aligned with one another and in registration with said apertures of said cylinder, I

a plurality of bifurcated pins disposed in said apertures, the length of said pins being adapted so that upon the insertion of said key means into said channel the interface between each bifurcated pin is in alignment with the interface between said cylinder and said plug means,

extending axially of a plurality of third spring means for urging said pins 1 radially inward, a lock bolt slidably disposed for radial motion in said cylinder alternately into and out of said locking the bottom, said second control means to slide outwardly of said housing and said dead bolt to withdraw from said opening under the tension of said first spring means.

9. The arrangement of claim 8 wherein said second control means comprises a push-button mounted adjacent to the exterior end of said lock bolt which extends into said locking slot.

10. The arrangement of claim 2 wherein said first control means comprises a push-button having said inclined surface on the end thereof interior to said housing. i

11. The arrangement of claim 2 wherein said first control means comprises a second cylinder lock having a second translatable rod at the end thereof interior to said housing, said end having said inclined surface thereon.

12. For use in latching an enclosure, a cylinder lock comprising an elongated cylindrical sleeve having a circumferential locking slot,

a spring-loaded cylinder slidably disposed in said sleeve, said cylinder having a circular axial channel therein which extends from one end of said sleeve and further having a rod fixedly secured thereto and extending out of the other end of said sleeve,

21 bifurcated circular plug rotatably disposed in said channel, said plug having separate inner and outer portions and having further an elongated keyway extending axially through said outer portion and at least into said inner portion,

said cylinder having a plurality of first radial apertures axially aligned with one another, at least one of said plug portions having a plurality of second radial apertures in registry with said first apertures,

a plurality of bifurcated, spring-loaded pins disposed in said apertures,

' a spring-loaded, slidable lock bolt disposed in saidv cylinder and having a transverse slot therein, and cam means on the innermost end face of said inner plug portion for engaging said lock bolt by said transverse slot so that upon insertion of a key into said keyway, and rotation of said plug portions together, said cam means lifts said lock bolt out of said locking slot, thereby permitting said cylinder to translate outwardly of said one end of said sleeve and said rod to translate inwardly towards 

1. A latching arrangement for a door or the like comprising a housing mounted on the interior side of said door, a dead bolt slidably disposed in said housing and adapted to be alternately extended into and withdrawn from an opening in a door jamb or the like, first lock means mounted in said door and having one end disposed exterior to said door and adapted to receive key means for unlocking said first lock means from the exterior side of said door, and further having the other end thereof disposed interior to said housing, each of said ends being inwardly and outwardly tranSlatable together in response to the locking and unlocking of said first lock means, first control means slidably mounted through a wall of said housing for applying a force to said dead bolt for extending same into said opening and for locking said first lock means from the interior side of said door, second control means mounted through said housing for unlocking said first lock means from the interior side of said door, and linkage means pivotally connected to both said first control means and said other end of said first lock means for extending said dead bolt in said opening in response to inward translation of said other end of said first lock means and of said first control means.
 2. The arrangement of claim 1 wherein said dead bolt has an inclined surface disposed at an obtuse angle to the outward direction of its motion, and said first control means has an inclined surface adapted to abut that of said dead bolt so that inward motion of said first control means causes extension of said dead bolt into said opening.
 3. The arrangement of claim 2 wherein said linkage means comprises a reverse-curve arm pivotally mounted in said housing at a point between said other end of said first lock means and said first control means.
 4. The arrangement of claim 3 including first spring means mounted in said housing for urging said dead bolt inwardly when in its extended position in said opening.
 5. The arrangement of claim 4 wherein said dead bolt is U-shaped having a pair of leg portions and an intermediate portion joining said leg portions, said intermediate portion including said inclined surface and said first spring means being connected to said pair of leg portions.
 6. The arrangement of claim 2 wherein said first lock means comprises a first cylinder lock.
 7. The arrangement of claim 6 wherein said first cylinder lock has a bifurcated plug adapted to receive said key means.
 8. The arrangement of claim 7 wherein said first cylinder lock comprises an elongated sleeve rigidly mounted in said door and to said housing and having a circumferential locking slot, a cylinder slidably mounted in one end of said sleeve and having a rod extending from the other end of said sleeve, and the end of said rod comprising the other end of said first lock means to which said linkage means is pivotally connected, second spring means for urging said cylinder outwardly of said sleeve, said cylinder having a plurality of radial apertures axially aligned with one another, and having further an elongated circular channel extending axially of said cylinder, circular cylindrical plug means rotatably disposed in said channel, said plug means comprising separate inner and outer plug portions axially aligned with one another and having an elongated keyway extending axially through said outer portion and at least into said inner portion for receiving said key means to couple together said plug portions for rotation, at least one of said plug portions having a plurality of radial apertures axially aligned with one another and in registration with said apertures of said cylinder, a plurality of bifurcated pins disposed in said apertures, the length of said pins being adapted so that upon the insertion of said key means into said channel the interface between each bifurcated pin is in alignment with the interface between said cylinder and said plug means, a plurality of third spring means for urging said pins radially inward, a lock bolt slidably disposed for radial motion in said cylinder alternately into and out of said locking slot, said lock bolt having a transverse slot therein, fourth spring means for urging said lock bolt into said locking slot, cam means disposed on the innermost end face of said inner plug portion and in said transverse slot so that, upon insertion of said key means into said keyway and rotation of said plug portions together, said cam means lifts said lock bolt out of said locking sLot, thereby to permit the following: said cylinder to be pushed outwardly by said second spring means, said rod to translate inwardly, said linkage means to rotate clockwise as viewed from the bottom, said second control means to slide outwardly of said housing and said dead bolt to withdraw from said opening under the tension of said first spring means.
 9. The arrangement of claim 8 wherein said second control means comprises a push-button mounted adjacent to the exterior end of said lock bolt which extends into said locking slot.
 10. The arrangement of claim 2 wherein said first control means comprises a push-button having said inclined surface on the end thereof interior to said housing.
 11. The arrangement of claim 2 wherein said first control means comprises a second cylinder lock having a second translatable rod at the end thereof interior to said housing, said end having said inclined surface thereon.
 12. For use in latching an enclosure, a cylinder lock comprising an elongated cylindrical sleeve having a circumferential locking slot, a spring-loaded cylinder slidably disposed in said sleeve, said cylinder having a circular axial channel therein which extends from one end of said sleeve and further having a rod fixedly secured thereto and extending out of the other end of said sleeve, a bifurcated circular plug rotatably disposed in said channel, said plug having separate inner and outer portions and having further an elongated keyway extending axially through said outer portion and at least into said inner portion, said cylinder having a plurality of first radial apertures axially aligned with one another, at least one of said plug portions having a plurality of second radial apertures in registry with said first apertures, a plurality of bifurcated, spring-loaded pins disposed in said apertures, a spring-loaded, slidable lock bolt disposed in said cylinder and having a transverse slot therein, and cam means on the innermost end face of said inner plug portion for engaging said lock bolt by said transverse slot so that upon insertion of a key into said keyway, and rotation of said plug portions together, said cam means lifts said lock bolt out of said locking slot, thereby permitting said cylinder to translate outwardly of said one end of said sleeve and said rod to translate inwardly towards the other end of said sleeve.
 13. The lock of claim 12 wherein said sleeve has an elongated axial slot therein and said cylinder includes a protruding member which extends into said slot to limit the extent of the translation of said cylinder, and at least one of said plug portions has a circumferential groove therein and said sleeve includes a radial post which rides in said groove to limit the extent of the rotation of said plug. 